trailer Medic - sanding Spindle - Photo 09

Any time you find a damaged bearing, check to make sure the bearing didn’t spin and damage the spindle surface. Ours had just a bit of roughness, which we polished smooth with some emery cloth. Before ordering new bearings, measure the spindle diameter or note the part number from the old bearings. Most 3,500lb axles will use inner and outer bearings with an id of 1-inch or an outer bearing with an id of 1-inch and an inner bearing with an id of 13⁄8-inch.